This invention relates generally to electrical plugs and, more particularly, to an ejector system for ejecting an electrical plug from an electrical power supply socket or socket.
Many domestic and industrial appliances, such as sweepers and floor polishers, are used over large areas and have very long power cords, which enable their use down long hallways to a location remote from where the power cord is plugged into a wall socket or socket. Other applications involve outdoor equipment, such as used in the building and construction trades, that require long lengths of electrical power cord to access remote work places. In order to continue use of such an appliance or equipment, the operator must walk a long distance to unplug the cord, then walk back and plug the cord into a sequence of widely spaced wall outlets to complete the sweeping, polishing, or other work task. This consumes an excessive amount of unproductive time by the appliance operator. In many instances the appliance operator, in an effort to dislodge the electrical power cord from the remote wall socket, pulls it repeatedly at a severe angle, which bends the prongs and/or tears the power cord components. This accounts for a significant amount of monetary damage to power cord components and to the wall sockets, and can disable the equipment until repaired.
There is a need for a product, which, in conjunction with an appliance, allows the appliance operator to easily unplug the power cord from the remote wall socket and does not require continual manual plugging and unplugging of the power cord from the remote wall socket. There have been many attempts to provide plug ejectors for enabling the remote unplugging of an appliance power cord by manipulating the power cord. Many of these have been patented, as evidenced by U.S. Pat. Nos. 2,394,618; 2,490,580; 2,456,548; 2,688,734; 2,696,594; 2,986,719; 3,475,715; 3,737,835; 3,936,123; 4,114,969; 4,045,106; 4,820,176 and 5,704,811. It is noteworthy that, although this problem was recognized at least as early as 1944, there has been no successful commercialized solution.
In my prior co-pending patent application Ser. No. 09/133015, I provide a device that enables an appliance operator to easily unplug an appliance power cord from a remote electrical wall socket by ejecting the appliance power cord plug from a remote location. This device utilizes a 4-conductor line cord and a separate switch to actuate an electric solenoid to eject an appliance plug from a wall socket. This necessitated extra expense via the use of extra and special equipment. That application anticipated the need for a device that operates off the standard appliance on off switch.
There is also a need for a plug ejector which is compact and inexpensive and which utilizes an appliance""s standard on/off switch to operate the plug ejector.
Older electrical sockets tend to be corroded and new sockets are manufactured with a wide range of socket aperture size, which can increase or decrease the frictional force with which it retains the power cord plug prongs. Also, power cord plugs that have been used many times may be bent or crimped due to many instances of off-axis removal. To accommodate the vast variety of forces needed to remove all power cord plugs from all sockets, the plug ejector, solenoid, or motor effecting the ejection must provide significant ejection force, which increases the size and cost of the plug ejector.
Thus, there is also a need for such a plug ejector that minimizes the force required to eject the plug.
There is also a need for a plug ejector which can be incorporated into new appliances as an option, or can be retrofitted to existing appliances and which will reliably eject a power cord plug from any wall socket.
It is therefore an object of this invention to provide a plug ejector which is compact and inexpensive, and which will reliably eject a plug from a socket.
It is another object to provide a plug ejector, which, when fitted to any appliance, allows the appliance operator to easily unplug the power cord from the remote wall socket and does not require continual manual plugging and unplugging of the power cord from the remote wall socket.
It is another object of this invention to provide a plug ejector that is produced with electronic circuitry that provides a xe2x80x9csmartxe2x80x9d sensor design to monitor the appliance power cord electrical characteristics and, upon sensing predetermined variations in these characteristics, energizes a system which ultimately ejects an appliance power cord plug from a remote electrical wall socket.
It is another object of this invention to provide a plug ejector that is produced with analog electronic circuitry to activate the plug ejector.
It is another object of this invention to provide a plug ejector that is produced with logic electronic circuitry to activate the plug ejector.
It is another object of this invention to provide a plug ejector that is produced with a microprocessor electronic circuitry to activate the plug ejector.
It is another object of this invention to provide a plug ejector that is produced with electronic circuitry, which does not require an activation switch other than the appliance or equipment on/off switch.
It is another object of this invention to provide a plug ejector which is produced with electronic circuitry that does not require an additional full length power wire incorporated within the standard power cord to allow the plug ejector to function properly, but utilizes an appliance""s existing power supply wiring and an appliance""s existing on/off switch to activate the plug ejector.
It is another object of this invention to provide a plug ejector that automatically resets itself to a ready position after an appliance operator activates the plug ejector to unplug the appliance power cord from a remote electrical wall socket.
It is another object of this invention to provide a plug ejector, which enables an appliance operator using the appliance at a work location to turn the appliance on and then off and on again without ejecting the appliance power cord from the remote wall socket.
It is another object of this invention to provide a plug ejector that is not affected by common transient pulsations in the electrical power characteristics within the appliance power cord and allows the use of the appliance or other types of equipment without disruption and without ejecting the power cord from the remote wall socket during these common electrical transient events.
It is another object of this invention to provide a plug ejector which is an integral part of a power cord plug assembly connected to the wall socket end of the power cord, which power cord will be assembled onto and made an integral part of an appliance or other type of equipment.
It is another object of this invention to provide a module, incorporating a plug ejector, that can be mounted directly onto a standard wall socket, which allows existing appliances or other types of equipment having conventional power cord plugs to be plugged into and ejected from the module.
It is another object of this invention to provide a separate plug ejector that can be connected to and is adaptable to existing appliance power cord plugs, thus allowing the appliance power cord to be plugged into the adaptor and ejected with the adaptor from the wall socket allowing the cord and adaptor to remain connected.
It is another object of this invention to provide such an adaptor which is incorporated into a power extension cord of any length.
This invention features a plug ejector for ejecting an electrical plug from an electric power supply socket that comprises an electric ejector motor having an ejector member and a controller for monitoring and sensing electrical power supply characteristics and for controlling energization of the motor. When a predetermined sequence of rapid changes in electrical power characteristics is sensed, the controller causes energization of the electric motor to extend the ejector member and eject the plug from the socket.
In one embodiment this invention also features a plug ejector that is carried in the line cord plug of an electrical appliance power supply cord to eject the electrical power supply cord plug from an electrical supply wall socket; comprising standard two or three prong plug assemblies, an impact resistant and non-conductive outer housing, an ejector member mounted internal to the housing for sliding movement between a retracted position and an extended position, an electrical or electronic circuit which senses a change in electrical characteristics, such as voltage, current, and/or power changes in the power supply cord, and triggers the electric motor, and said electric motor moves the ejector member from retracted to extended position impacts the face plate of the wall socket and thereby ejects the plug prongs from the wall socket apertures. Preferably, the electric motor is a solenoid or similar impact device. The plug prongs are connected to the plug ejector motor electrical power leads in a normal fashion and then to power terminals of a remote electric appliance operating switch by an elongated electric power supply cord. The plug ejector electronic components sense rapid sequential on-off operation of the appliance operating switch and energize the electric motor projecting the internal member against the wall socket face plate to eject the plug prongs from the wall socket.
In another embodiment, the plug ejector is a self-contained module having both socket slots for receiving prongs of an electric appliance power cord and also having its own set of electrical prongs to connect to the wall socket, thereby electrically connecting the appliance to the wall socket through the plug ejector. In operation, the module is semi-permanently secured to the wall socket and ejects the plug and attached appliance power cord, while the module remains plugged into the wall socket.
In a further embodiment, this invention features a plug ejector carried by an adaptor, which receives the standard plug of any appliance line cord and is plugged into a wall or other power supply socket. In operation, the adaptor is ejected from the socket and remains with the line cord.
In another embodiment, the plug ejector is an integral part of a separate power extension cord of any length.